Apostolic Nuncio to Cologne

The Apostolic Nunciature to Cologne (also Italian: Nunziatura di Germania inferiore, i.e. Nunciature of Lower Germany) was an ecclesiastical office of the Roman Catholic Church established in 1584. The nuncios were accredited to the Achbishop-Electorates of Cologne, Mainz and Trier. It was a diplomatic post of the Holy See, whose representative was called the Apostolic Nuncio at Cologne, one of the states of the Holy Roman Empire. The office of the nunciature has been located in Cologne until 1795, when France occupied the city. The last nuncio officiating until 1804, resided in Augsburg, while the Archbishop-Electorate had been dissolved in 1803.

Two nuncios and one apostolic delegate at Cologne later became popes, to wit Pope Urban VII, Pope Alexander VII and Pope Leo XII.

An Apostolic Nuncio at Cologne was appointed in 1584 on the instigation of Emperor Rudolph II of the Holy Roman Empire. Following the Council of Trient, apostolic delegates had already earlier been appointed at Cologne in order to contain the spreading of Protestantism in the Empire. The Archbishop-Electorate of Cologne was chosen for being a stronghold of Catholicism in the northwest of the Empire in vicinity to areas, where Calvinism (Bremen, Dutch Republic, East Frisia, Lippe) and Lutheranism (elsewhere in Northern Germany) were gaining more and more support. The Rhenish Archbishop-Electorates were further important as providing already three of the then seven votes within the election body for the imperial successors.

...
Wikipedia